KR20130100734A - Composition for forming aluminum-containing film and method for forming aluminum-containing film - Google Patents

Abstract

PURPOSE: An aluminum containing film forming composite and a forming method thereof are provided to obtain an aluminum oxide film and an aluminum nitride film which have a higher purity than the conventional aluminum oxide film and aluminum nitride film. CONSTITUTION: A forming method of an aluminum containing film comprises the following steps. A coating layer is formed by coating an aluminum containing film formation composite, which is written in claim 1, on a gas. A film which contains carbon and aluminum is formed by heating the coating layer with one treatment which is selected from a group comprising electron irradiation, UV irradiation, and plasma. An oxide aluminum film is formed by performing hydrothermal treatment on the film which is obtained from the film forming process. The gas has the surface which is coated with a film containing aluminum or a transition metal.

Description

COMPOSITION FOR FORMING ALUMINUM-CONTAINING FILM AND METHOD FOR FORMING ALUMINUM-CONTAINING FILM}

The present invention relates to a composition for forming an aluminum containing film and a method for forming an aluminum containing film.

Aluminum oxide (alumina) is widely used as a protective film and an insulating film in a semiconductor device typified by DRAM (dynamic random access memory) because of its high insulation and compactness. Moreover, the use of the gap layer, the protective film of a thin film magnetic head, the protective film of a metal component, and the gas barrier film on a plastic film is also examined.

On the other hand, since aluminum nitride has high thermal conductivity and insulation property, not only the use as a heat radiation board | substrate is examined in semiconductor devices, but the application as an optical material is also expected.

Conventionally, the sputtering method and the chemical vapor deposition method are widely used as a formation method of aluminum oxide and aluminum nitride.

For example, Patent Document 1 proposes a method of forming an aluminum oxide film for sputtering an aluminum-containing target in a gas containing a fluorine atom.

In addition, Patent Document 2 proposes a film forming method for forming an insulating film in which aluminum oxide and titanium oxide are alternately laminated by atomic layer epitaxial growth, and the aluminum oxide film is formed of aluminum oxide and water as a source gas. It is generated using

In addition, Patent Document 3 proposes a method of forming an aluminum-containing film (aluminum oxide film, aluminum nitride film or aluminum oxynitride film) by a CVD method using an unnatural amino aluminum precursor on a substrate.

However, such an aluminum-containing film forming method by sputtering or chemical vapor deposition is expensive because it requires expensive devices such as vacuum chambers and high-voltage current devices. In addition, there has been a problem that application to a large diameter gas is difficult. In addition, with the recent miniaturization of semiconductor devices, there have been problems such as occurrence of defects in the film and deterioration in step coverage during film formation on the narrow trench substrate.

On the other hand, the coating method of apply | coating the solution of the aluminum containing compound or polymer which becomes a raw material to a board | substrate, and heat-processing etc. and obtaining an aluminum containing film can obtain a target film easily with a cheap apparatus compared with the said film-forming method. . In addition, since the said coating method is considered to be excellent in the film-forming property, embedding property, and level | step difference coating property to a narrow trench gas phase, it is anticipated that it will be widely used in the future.

As an example of the coating method, Patent Document 4 applies a compound having an Al-N bond to a skeleton, or a solution of the compound, to a base material within a range of 50 ° C to 1000 ° C in an atmosphere containing an oxygen-containing gas. A method for producing a heated alumina film has been proposed, and an example in which a solution obtained by dissolving iminoalan in an organic solvent as a solution of a compound having an Al—N bond in the skeleton is used as a film forming composition.

Japanese Patent Publication No. 9-316631 Japanese Patent Laid-Open No. 2001-220294 Japanese Patent Publication No. 2006-526705 Japanese Patent Publication No. 2007-210825

However, alan or alkylaluminum or the like used in the conventional coating method has a low reactivity, and there is a problem that metal aluminum, nitrogen, carbon components, etc. are likely to remain in a part of the obtained aluminum oxide film or aluminum nitride film. For example, since iminoalan described in Patent Document 4 is an oligomer, the reactivity at the time of thermal firing is low, and although baking is performed at a high temperature of 700 degreeC under oxygen atmosphere, the obtained aluminum oxide film contains nitrogen and carbon. In the point that is confirmed, in order to obtain a pure aluminum oxide film using the said iminoalan, baking at 800 degreeC or more is required for 3 hours or more in oxygen atmosphere.

It is an object of the present invention to provide a composition for forming an aluminum-containing thin film which is highly reactive and which can more easily obtain a high purity aluminum oxide film or an aluminum nitride film as compared with the conventional method.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to solve the said subject, according to the composition for aluminum containing film formation containing the organic aluminum compound and organic solvent which have a specific structure, it discovered that the said subject can be solved and completed this invention. It was.

That is, this invention provides the following [1]-[10].

[1] An aluminum-containing film-forming composition containing an organoaluminum compound having a structure represented by the following formula (1) and an organic solvent.

(In formula (1), R ¹ to R ⁶ may be a hydrogen atom or a hydrocarbon group, may be the same or different, and R ⁿ (n is an integer of 1 to 6) may be connected to each other.

[2] A coating step of applying the composition for forming an aluminum-containing film according to [1] to form a coating layer on the base, and heating the coating layer with an inert gas or a reducing gas atmosphere, and irradiating with ultraviolet rays. And a curing step of forming an aluminum nitride film by performing at least one treatment selected from the group consisting of plasma.

[3] The method for forming an aluminum-containing film according to the above [2], wherein the base is covered with a film containing aluminum or a transition metal on the surface of the base body.

[4] A coating step of applying the composition for forming an aluminum-containing film according to the above [1] to form a coating layer on the substrate, and heating the coating layer in an oxidizing atmosphere, electron beam irradiation, ultraviolet irradiation, and plasma. The formation method of the aluminum containing film containing the hardening process of forming an aluminum oxide film by performing at least 1 sort (s) of treatment chosen from the group.

[5] The method for forming an aluminum-containing film according to the above [4], wherein the base is covered with a film containing aluminum or a transition metal on the surface of the base body.

[6] The method for forming an aluminum-containing film according to the above [4], wherein the oxidative atmosphere is an oxidizing gas atmosphere.

[7] The method for forming an aluminum-containing film according to the above [6], wherein the base is covered with a film containing aluminum or a transition metal on the surface of the base body.

[8] The method for forming an aluminum-containing film according to the above [4], wherein the oxidative atmosphere is an air atmosphere.

[9] The method for forming an aluminum-containing film according to [8], wherein the base is covered with a film containing aluminum or a transition metal on the surface of the base body.

[10] a coating step of applying the composition for forming an aluminum-containing film according to [1] to form a coating layer on a substrate; and the coating layer selected from the group consisting of heating, electron beam irradiation, ultraviolet irradiation, and plasma. A film forming step of forming a film containing carbon and aluminum by performing at least one kind of treatment, and a post-treatment step of forming an aluminum oxide film by performing hydrothermal treatment on the film obtained in the film forming step. A method of forming an aluminum containing film.

[11] The method for forming an aluminum-containing film according to the above [10], wherein the base is covered with a film containing aluminum or a transition metal on the surface of the base body.

The composition for forming an aluminum-containing film of the present invention is highly reactive, and an aluminum oxide film or an aluminum nitride film of high purity can be obtained more easily than in the conventional method.

The composition for aluminum containing film formation of this invention contains the organoaluminum compound which has a structure represented by following General formula (1), and an organic solvent.

(In formula (1), R ¹ to R ⁶ may be a hydrogen atom or a hydrocarbon group, may be the same or different, and R ⁿ (n is an integer of 1 to 6) may be connected to each other.

The nitrogen-containing cyclic group may be formed by connecting R ⁿ (n is an integer of 1 to 6) bonded to one nitrogen atom of the formula (1) with each other.

In addition, in this specification, the line which shows the bond between atoms in a structural formula is not limited to a covalent bond.

As an example of the organoaluminum compound which has a structure represented by the said General formula (1), the organoaluminum compound represented by following General formula (2) or following General formula (3) is mentioned, for example.

(In Formula (2), R ⁷ is a hydrogen atom or a hydrocarbon group, and may be the same or different.)

In said Formula (2), R <^7> , Preferably it is a hydrogen atom or a C1-C12 monovalent hydrocarbon group, More preferably, it is a C1-C4 monovalent hydrocarbon group. Here, a C1-C12 monovalent hydrocarbon group is a C1-C12 branched or unbranched alkyl group, alkenyl group, alkynyl group, and aryl group, for example.

Among them, the methyl group, ethyl group, propyl group, and isopropyl group are preferably used from the viewpoint of ease of decomposition of the complex when the heating, electron beam irradiation, ultraviolet irradiation, plasma or the like is performed.

(In said Formula (3), R <^8> is a hydrocarbon group and may be same or different, respectively.)

In said general formula (3), R <^8> , Preferably it is a C1-C12 bivalent hydrocarbon group, More preferably, it is a C1-C4 bivalent hydrocarbon group. Here, with a C1-C12 bivalent hydrocarbon group, a C1-C12 branched or unbranched alkylene group, an alkenylene group, an aralkylene group, an arylene group is mentioned, for example.

Especially, from an easy viewpoint of the decomposition | disassembly of a complex at the time of processing, heating, electron beam irradiation, ultraviolet irradiation, a plasma, etc., Preferably, they are an ethylene group and a propylene group.

The organic solvent contained in the composition for forming an aluminum-containing film of the present invention is not particularly limited as long as it dissolves the organoaluminum compound and does not react with them. For example, a hydrocarbon solvent, an ether solvent, another polar solvent, etc. can be used.

Examples of the hydrocarbon solvent include hydrides of n-pentane, cyclopentane, n-hexane, cyclohexane, n-heptane, cycloheptane, n-octane, cyclooctane, decane, cyclodecane, dicyclopentadiene, Benzene, toluene, xylene, durene, indene, tetrahydronaphthalene, decahydronaphthalene, squalane and the like.

As said ether solvent, for example, diethyl ether, dipropyl ether, dibutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether , Diethylene glycol methyl ethyl ether, tetrahydrofuran, tetrahydropyran, bis (2-methoxyethyl) ether, p-dioxane, anisole, 2-methylanisole, 3-methylanisole, 4-methylaniline Sol, pentol, 2-methylpentol, 3-methylpentol, 4-methylpentol, veratrol, 2-ethoxyanisole, 1,4-dimethoxybenzene and the like.

As said polar solvent, methylene chloride, chloroform, etc. are mentioned, for example.

These organic solvents may be used alone or in combination of two or more thereof.

Among the organic solvents, preferred are a hydrocarbon solvent or a mixed solvent of a hydrocarbon solvent and an ether solvent in view of solubility and stability of the solution to be formed. The hydrocarbon solvent is preferably n-pentane, cyclopentane, n-hexane, cyclohexane, n-heptane, cycloheptane, n-octane, n-decane, benzene, toluene or xylene. As an ether solvent, Preferably, diethyl ether, dipropyl ether, dibutyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, tetrahydrofuran, tetrahydropyran, anisole, 2-methylanisole, 3 Methylanisole, 4-methylanisole, pentol, veratrol, 2-ethoxyanisole, 1,4-dimethoxybenzene.

<Formation Method of Aluminum-Containing Film>

As a method for forming the aluminum-containing film of the present invention, a coating step of applying the composition for forming an aluminum-containing film on a substrate to form a coating layer, heating the coating layer under a specific atmosphere, electron beam irradiation, ultraviolet irradiation and The formation method of the aluminum containing film containing the hardening process of forming an aluminum containing film by performing at least 1 sort (s) of process chosen from the group which consists of plasma is mentioned.

There is no restriction | limiting in particular in the material, shape, etc. of the material which comprises the said base | substrate (the base body, when having a base film mentioned later). When the material of a base | substrate employ | adopts heat processing in the conversion process to the aluminum containing film of a coating layer, it is preferable that it can endure the heat processing. The shape of the base on which the coating layer is formed is not particularly limited to blocks, plates, films, and the like. The surface of the base on which the coating film is formed may be flat or may be a stepped non-planar surface. The gas may also have recesses on its surface. In addition, the "concave part" has the concept of including both the wiring groove | channel or electrode groove (trench) formed on the base body, and wiring connection hole (hole).

As a material of a base body, glass, a metal, a plastic, a ceramic etc. are mentioned, for example. As glass, quartz glass, borosilicate glass, soda glass, lead glass, etc. are mentioned, for example. As a metal, stainless steel is mentioned besides gold, silver, copper, nickel, silicon, aluminum, iron, etc., for example. As plastics, polyimide, polyether sulfone, etc. are mentioned, for example.

The base may be coated with a film (hereinafter, also referred to as a "base film") whose surface of the base body contains aluminum or a transition metal. When the base has the base film, the film-forming property of the aluminum-containing film onto the base can be made better.

The base film is an organometallic compound containing at least one metal atom selected from the group consisting of aluminum and a transition metal in advance in the body, except for an organoaluminum compound having a structure represented by the formula (1). It is formed by applying a solution (hereinafter also referred to as "composition for base film formation") containing a layer), followed by heat treatment.

The organometallic compound containing the aluminum atom excludes an organoaluminum compound having a structure represented by the formula (1), and examples thereof include aluminum alkoxides, aluminum alkylates, and β-diketone complexes of aluminum. Can be.

As said transition metal, a titanium atom, a palladium atom, etc. are mentioned, for example.

As an organometallic compound containing the said titanium atom, titanium alkoxide, the titanium compound which has an amino group, the (beta) -diketone complex of titanium, the titanium compound which has a cyclopentadienyl group, the titanium compound which has a halogen atom, etc. are mentioned, for example. Can be mentioned.

Examples of the organometallic compound containing the palladium atom include palladium complexes having halogen atoms, acetates of palladium, β-diketone complexes of palladium, complexes of palladium with compounds having conjugated carbonyl groups, and phosphine complexes of palladium. Etc. can be mentioned.

As an organometallic compound containing the said aluminum atom, it is an aluminum alkoxide, for example, aluminum ethoxide, aluminum isopropoxide, aluminum-n-butoxide, aluminum-s-butoxide, aluminum-t-butoxide Seeds, aluminum ethoxyethoxyethoxide, aluminum phenoxide and the like;

As aluminum alkylate, For example, aluminum acetate, aluminum acrylate, aluminum methacrylate, aluminum cyclohexane butyrate, etc .;

As β-diketone complex of aluminum, for example, pentane-2,4-diketoaluminum, hexafluoropentane-2,4-diketoaluminum, 2,2,6,6-tetramethylheptane-3,5 -Diketoaluminum, bis (ethoxybutane-1,3-diketo) aluminum s-butoxide, (ethoxybutane-1,3-diketo) aluminumdi-s-butoxide, (ethoxybutane-1 , 3-diketo) aluminum diisopropoxide, and the like.

As an organometallic compound containing the said titanium atom, the compound represented by following formula (4)-8 is mentioned, for example.

&Lt; Formula 4 >

(In Formula 4, R ⁷ is an alkyl group having 1 to 10 carbon atoms, a phenyl group, a halogenated alkyl group or a halogenated phenyl group.)

&Lt; Formula 5 >

(In Formula 5, R ⁸ is the same as R ⁷ of Formula 4, L is a group represented by Formula 9, R ⁹ and R ¹⁰ are the same or different, an alkyl group having 1 to 10 carbon atoms, a phenyl group, Alkoxy group, halogenated alkyl group or halogenated phenyl group, x is an integer of 0 to 3)

&Lt; Formula 9 >

(6)

(In Formula 6, R ¹¹ is an alkyl group or a phenyl group, X is a halogen atom, y is an integer of 0 to 3)

&Lt; Formula 7 >

(In Formula 7, R ¹² is an alkyl group or a phenyl group.)

(8)

(In Formula 8, Cp is a cyclopentadienyl group, Y is a halogen atom or an alkyl group, n is an integer of 1 to 4)

In Formulas 4 and 5, R ⁷ and R ⁸ are preferably methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, t-butyl group, methoxy group, ethoxy group, n-propoxy Time period, i-propoxy group, n-butoxy group, t-butoxy group, hexyl group, cyclohexyl group, phenoxy group, methylphenoxy group, trifluoromethyl group, more preferably methyl group, ethyl group, n-propyl group , i-propyl group, n-butyl group, t-butyl group, hexyl group, cyclohexyl group, and phenyl group.

In Formula 9, R ⁹ and R ¹⁰ are preferably methyl, ethyl, n-propyl, i-propyl, n-butyl, t-butyl, methoxy, ethoxy or n-propoxy. A time period, i-propoxy group, n-butoxy group, t-butoxy group, phenoxy group, methylphenoxy group, torofluoromethyl group, more preferably methyl group, ethyl group, i-propyl group, t-butyl group, methok It is a time period, an ethoxy group, i-propoxy group, t-butoxy group, and a trifluoromethyl group.

Examples of the titanium compound represented by Chemical Formula 4 include titanium methoxide, titanium ethoxide, titanium-n-propoxide, titanium-n-nonyloxide, titanium stearyl oxide, and titanium isopropoxide. , Titanium-n-butoxide, titanium isobutoxide, titanium-t-butoxide, titanium trimethylsiloxide, titanium-2-ethylhexoxide, titanium methoxypropoxide, titanium phenoxide, titanium methylphenoxide, Titanium fluoromethoxide, titanium chlorophenoxide and the like.

Examples of the titanium compound represented by Formula 5 include tetrakis (penta-2,4-diketo) titanium and tetrakis (2,2,6,6-tetramethylhepta-3,5-diketo). Titanium, tetrakis (1-ethoxybutane-1,3-diketo) titanium, tetrakis (1,1,1,5,5,5-hexafluoropenta-2,4-diketo) titanium, ( 2,2-dimethylhexa-3,5-diketo) titanium, bis (penta-2,4-diketo) titanium dimethoxide, bis (2,2,6,6-tetramethylhepta-3,5- Diketo) titanium dimethoxide, bis (1-ethoxybutane-1,3-diketo) titaniumdimethoxide, bis (1,1,1,5,5,5-hexafluoropenta-2,4 -Diketo) titanium dimethoxide, (2,2-dimethylhexa-3,5-diketo) titanium dimethoxide, bis (penta-2,4-diketo) titaniumdii-propoxide, bis ( 2,2,6,6-tetramethylhepta-3,5-diketo) titaniumdii-propoxide, bis (1-ethoxybutane-1,3-diketo) titaniumdii-propoxide, Bis (1,1,1,5,5,5-hexafluoropenta-2,4-diketo) titaniumdi i-propoxide, (2,2-dimethylhexa-3,5-diketo) titaniumdii-propoxide, and the like.

Examples of the titanium compound represented by Chemical Formula 6 include trimethoxy titanium chloride, triethoxy titanium chloride, tri-n-propoxytitanium chloride, tri-i-propoxytitanium chloride and tri-n-butoxy Titanium chloride, tri-t-butoxytitanium chloride, triisostearoyl titanium chloride, dimethoxytitanium dichloride, diethoxy titanium dichloride, di-n-propoxytitanium dichloride, di-i-propoxytitanium di Chloride, di-n-butoxytitanium dichloride, di-t-butoxytitanium dichloride, diisostearoyltitanium dichloride, methoxytitanium trichloride, ethoxytitanium trichloride, n-propoxytitanium trichloride , i-propoxytitanium trichloride, n-butoxytitanium trichloride, t-butoxytitanium trichloride, isostaroyl tita Nium trichloride, titanium tetrachloride, etc. are mentioned.

Examples of the titanium compound represented by the formula (7) include tetrakis (dimethylamino) titanium, tetrakis (diethylamino) titanium, tetrakis (di-t-butoxyamino) titanium and tetrakis (di-i -Propoxyamino) titanium, tetrakis (diphenylamino) titanium, etc. are mentioned.

As the titanium compound represented by the formula (8), for example, dicyclopentadienyl titanium dichloride, dicyclopentadienyl titanium dibromide, cyclopentadienyl titanium trichloride, cyclopentadienyl titanium tribromide, and dicyclo Pentadienyl dimethyl titanium, dicyclopentadienyl diethyl titanium, dicyclopentadienyl di-t-butyl titanium, dicyclopentadienylphenyl titanium chloride, dicyclopentadienyl methyl titanium chloride, and the like.

As an organometallic compound containing the said palladium atom, As a palladium complex which has a halogen atom, For example, allyl palladium chloride, dichlorobis (acetonitrile) palladium, dichlorobis (benzonitrile) palladium etc .;

As acetate of palladium, For example, palladium acetate etc .;

As the β-diketone complex of palladium, for example, pentane-2,4-dionate palladium, hexafluoropentanedionate palladium and the like;

As a complex of palladium and the compound which has a conjugated carbonyl group, For example, bis (dibenzylidene acetone) palladium etc .;

As the phosphine complex of palladium, for example, bis [1,2-bis (diphenylphosphino) ethane] palladium, bis (triphenylphosphine) palladium chloride, bis (triphenylphosphine) palladium acetate, diacetatebis (Triphenylphosphine) palladium, dichloro [1,2-bis (diphenylphosphine) ethane] palladium, trans-dichlorobis (tricyclohexylphosphine) palladium, trans-dichlorobis (triphenylphosphine) palladium, Trans-dichlorobis (tri-o-tolylphosphine) palladium, tetrakis (triphenylphosphine) palladium, and the like.

Among the organometallic compounds described above, titanium isopropoxide, aluminum isopropoxide, bis (ethoxybutane-1,3-diketo) titanium diisopropoxide and tetra (pentane-2,4- Diketo) titanium, pentane-2,4-diketopalladium, hexafluoropentane-2,4-diketopalladium, pentane-2,4-diketoaluminum or hexafluoropentane-2,4-diketoaluminum to be.

As a solvent used for the solution of the organometallic compound containing at least 1 sort (s) of metal atoms (for example, titanium, palladium, etc.) chosen from the group which consists of these aluminum and a transition metal, if the said organometallic compound can be melt | dissolved, Any solvent can be used. Examples of these solvents include ethers, esters having ether groups, hydrocarbons, alcohols, aprotic polar solvents, and mixed solvents thereof.

As said ether, For example, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, etc .;

Examples of the ester having an ether group include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, 2-acetoxy-1-methoxypropane, and the like. ;

As said hydrocarbon, For example, toluene, xylene, hexane, cyclohexane, octane, decalin, tetralin, durene, etc .;

As said alcohol, For example, methanol, ethanol, propanol, etc .;

Examples of the aprotic polar solvents include N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, hexamethylphosphoramide, γ-butyrolactone, and the like. Can be.

Content in solution of the said organometallic compound becomes like this. Preferably it is 0.1-10 mass%, More preferably, it is 0.1-5 mass%. In addition, it is preferable to use what removed this water and oxygen as this solvent.

Application | coating to the base | substrate main body of these composition for base film formation can be performed by a suitable method, such as a spin coating method, a roll coating method, a curtain coating method, an immersion coating method, a spray method, a droplet discharge method, etc., for example.

When the base body has a trench structure, when the opening width is 300 nm or less, and when the aspect ratio of the trench is 5 or more, after applying the composition for forming a base film to the base body, the gas is applied for a while than the environmental pressure at the time of application. By putting it under low pressure, the composition for base film formation can be apply | coated more uniformly inside a trench. As a specific technique, the substrate is formed under a pressure (hereinafter, referred to as "second pressure") that is smaller than the pressure (hereinafter referred to as "first pressure") when the composition for forming a base film is applied onto a base body having a trench. Keep it. The second pressure is preferably 1 to 70%, more preferably 10 to 40% with respect to the first pressure. For example, as a 2nd pressure when the pressure at the time of application | coating is 1.01x10 <^5> Pa (normal pressure), Preferably it is 1.01 * 10 <^3> -7.09 * 10 <^4> Pa, More preferably, 1.01 * 10 <^4> To 4.05 × 10 ⁴ mW. As time to keep a gas under 2nd pressure, Preferably it is for 10 second-10 minutes, More preferably, it is for 10 seconds-1 minute. After maintaining the gas at the second pressure, it is preferably provided to the next heating process after returning the pressure with an inert gas, but after reducing this pressure to maintain the same pressure, a series of operations to return the pressure You can repeat this several times. The pressure raising time for returning from the second pressure to the first pressure is preferably 3 seconds to 5 minutes, and more preferably 5 seconds to 1 minute. The number of repetitions is preferably 10 times or less from the viewpoint of both the uniformity of the film and workability, and more preferably 5 times or less from the viewpoint of workability. The base film thus formed is then heated. Heating temperature becomes like this. Preferably it is 30-350 degreeC, More preferably, it is 40-300 degreeC. The heating time is preferably 5 to 90 minutes, more preferably 10 to 60 minutes. The atmosphere around the film | membrane from the said application process to completion | finish of a heating process becomes like this. Preferably it is inert gas, such as nitrogen, helium, argon. Moreover, it can also be implemented in the atmosphere which mixed reducing gas, such as hydrogen, and oxidizing gas, such as oxygen, as needed.

The thickness of these base films is a film thickness after heating, Preferably it is 0.001-5 micrometers, More preferably, it is 0.005-0.5 micrometer.

As a method of apply | coating the composition for aluminum containing film formation of this invention on the base mentioned above, it is suitable, for example, spin coating method, roll coating method, curtain coating method, dip coating method, spray method, droplet ejection method, etc. Method can be used. As such an application | coating process, the application | coating conditions which make the composition for aluminum film formation even to every corner of a base | substrate are employ | adopted according to the shape, size, etc. of a base | substrate. For example, when the spin coating method is adopted as the coating method, the spin speed of the spinner is preferably 300 to 2,500 rpm, more preferably 500 to 2,000 rpm. Moreover, when a base has a recessed part, the variation of the environmental pressure after application | coating as mentioned above can also be employ | adopted in application | coating of the composition for base film formation.

After the said coating process, in order to remove low boiling point components, such as a solvent contained in the apply | coated composition for aluminum containing film formation, you may heat-process. Although the temperature and time to heat differ with the kind of solvent to be used and boiling point (vapor pressure), it can be made into 5 to 90 minutes at 100-350 degreeC, for example. At this time, the solvent can be removed at a lower temperature by depressurizing the whole system. The conditions of heat processing under reduced pressure, Preferably it is 10 to 60 minutes at 100-250 degreeC.

Subsequently, an aluminum-containing film can be formed on the substrate by performing at least one treatment selected from the group consisting of heating, electron beam irradiation, ultraviolet irradiation, and plasma under a specific atmosphere with respect to the coating layer formed by the above-described method. .

Here, the aluminum containing film formed on a base is an aluminum oxide film or an aluminum nitride film. In addition, the aluminum containing film does not contain metal aluminum.

Moreover, arbitrary aluminum containing films (aluminum oxide film, aluminum nitride film) can be formed on a base by making the atmosphere at the time of performing the said heating, electron beam irradiation, ultraviolet irradiation, or plasma processing into a specific atmosphere.

Specifically, a high purity aluminum oxide film can be obtained by performing heat treatment or the like in an oxidizing atmosphere.

As said oxidizing atmosphere, an oxidizing gas atmosphere, an air atmosphere, etc. are mentioned, for example. Among them, from the viewpoint of ease of operation and economy, preferably air.

As said oxidizing gas, oxygen, ozone, an oxygen radical, carbon dioxide, nitrogen dioxide, water vapor, etc. are mentioned, for example. Among them, from the viewpoint of economics, it is preferably water vapor.

In addition, a high purity aluminum nitride film can be obtained by performing heat treatment or the like under an inert gas atmosphere or a reducing gas atmosphere.

Here, with an inert gas, nitrogen, helium, argon etc. are mentioned, for example. Examples of the reducing gas include hydrogen and ammonia. Among them, from the viewpoint of high purity, heating is preferably performed in an ammonia atmosphere.

The temperature at the time of performing heat processing becomes like this. Preferably it is 60 degreeC or more, More preferably, it is 70 degreeC-600 degreeC, Especially preferably, it is 100 degreeC-500 degreeC. The heating time is preferably 30 seconds to 120 minutes, more preferably 1 to 90 minutes, and particularly preferably 10 to 60 minutes.

In addition, the film formation process mentioned later may be performed before a hardening process, and the hardening process mentioned above may be performed with respect to the film | membrane containing carbon and aluminum instead of an application layer.

Moreover, as another formation method of the aluminum containing film of this invention, the coating process of apply | coating the said composition for aluminum containing film formation on the said base, and forming a coating layer, heating the said coating layer, electron beam irradiation, ultraviolet irradiation, and plasma A film forming step of forming a film containing carbon and aluminum by performing at least one treatment selected from the group consisting of a group, and a post-treatment step of forming an aluminum oxide film by performing a hydrothermal treatment on the film obtained by the film forming step. The formation method of the aluminum containing film containing these is mentioned.

By performing a film formation process, the film | membrane containing a small amount of carbon and aluminum is formed on a base body.

The atmosphere at the time of performing a film formation process is not specifically limited, For example, it can carry out under the above-mentioned oxidizing atmosphere, inert gas atmosphere, or reducing gas atmosphere. Especially, it is inert gas atmosphere preferably. Moreover, in inert gas, More preferably, it is nitrogen.

The temperature at the time of performing heat processing in a film formation process becomes like this. Preferably it is 60 degreeC or more, More preferably, it is 70 degreeC-600 degreeC, Especially preferably, it is 100 degreeC-500 degreeC. The heating time is preferably 30 seconds to 120 minutes, more preferably 1 to 90 minutes, and particularly preferably 10 to 60 minutes.

By performing hydrothermal treatment on the film obtained by the film forming step, a high purity aluminum oxide film can be formed on the substrate.

Here, the hydrothermal treatment is a treatment carried out in the presence of highly reactive water under high temperature and high pressure (under 100 ° C. and atmospheric pressure exceeding 1 atmosphere).

Specifically, the gas in which the film | membrane containing a small amount of carbon and aluminum is formed is heat-processed by autoclave etc. at the temperature of 100 to 300 degreeC, Preferably it is 130 to 250 degreeC for 2 to 5 hours. The pressure condition is an atmospheric pressure exceeding 1 atmosphere, preferably 2-3 atmospheres. By performing the hydrothermal treatment under the above conditions, an aluminum containing film containing aluminum oxide can be formed on the substrate.

In addition, a basic compound can also be added as a catalyst when performing a hydrothermal treatment. As a basic compound, amines, ammonia, sodium hydroxide, potassium hydroxide, etc. are mentioned, for example. Among them, from the viewpoint of having volatility and easy removal, they are preferably amines and ammonia, and more preferably ammonia.

When using ammonia as a basic compound, content of ammonia is preferably 0.0001 mass part-100 mass parts, More preferably, it is 0.1 mass part-50 mass parts with respect to 100 mass parts of compositions for aluminum containing film formation.

[Example]

Hereinafter, the present invention will be described concretely with reference to Examples, but the present invention is not limited to these Examples. In addition, all the following operations were performed in the dry nitrogen atmosphere except the case mentioned specially. In addition, all the used solvents were dehydrated previously by molecular sieve 4A (made by Union Showa Co., Ltd.), and also degassed by bubbling nitrogen gas.

In addition, "%" in the following sentences is a mass reference | standard unless there is particular notice.

Synthesis Example 1

100 ml (0.20 mol) of THF solution containing dimethylamine in a content of 2.0 mol / L was added to a three neck flask, and 200 ml of THF was added thereto and diluted. After cooling this dilution liquid at -40 degreeC, 125 ml (0.20 mol) of hexane solutions which contain n-butyllithium in content of 1.6 mol / L were added here for 30 minutes, and the lithium dimethylamide solution was obtained. 8.9 g (0.067 mol) of aluminum chloride was added to another flask, and 60 ml of THF and 60 ml of diethyl ether were sequentially added thereto to dissolve aluminum chloride to obtain an aluminum chloride solution. While the lithium dimethylamide solution was cooled in an ice bath, the prepared aluminum chloride solution was added over 30 minutes. Subsequently, after stirring at room temperature for 3 hours, the mixture was concentrated under reduced pressure to completely remove the solvent. The solid remaining in the flask was extracted with 200 ml of hexane and then filtered, and the filtrate was concentrated under reduced pressure again to obtain 10.4 g of an off-white solid material. As a result of analysis by NMR and analytical method, it was confirmed that this substance was a compound which has the following structure. In addition, the yield was 97%.

(In the compound which has the said structure, "Me" means a methyl group.)

[Synthesis Example 2]

0.51 g (0.014 mol) of lithium aluminum hydride and 130 ml of diethyl ether were added to a three neck flask to obtain a suspension. A solution obtained by mixing 4.92 g (0.070 mol) of pyrrolidine and 50 ml of diethyl ether was added to this suspension at room temperature. After the addition, the mixture was stirred at room temperature for 2 hours, and then concentrated under reduced pressure to remove the solvent once. Then, 80 ml of THF was added to the flask and redissolved. Then, a solution obtained by mixing and dissolving 0.60 g (0.0046 mol) of aluminum chloride, 16 ml of THF and 8 ml of diethyl ether was added at room temperature. After the addition, the mixture was stirred at room temperature for 6 hours, concentrated under reduced pressure to remove the solvent, and then 80 ml of toluene was added and extracted. After insoluble matter was removed by filtration, the filtrate was concentrated under reduced pressure to obtain 3.5 g of an off-white solid. As a result of NMR and elemental analysis, it was confirmed that this substance was a compound having the following structure. In addition, the yield was 80%.

[Synthesis Example 3]

3.80 g of lithium aluminum hydride was charged into a 200 ml three-neck flask containing a magnetic stirrer. The three connection ports of the three-necked flask were connected to a 100 ml powder addition funnel, a suction stopper three-way cock and a glass stopper connected to a nitrogen stream, respectively. After 17.80 g of hydrochloric acid triethylamine was charged into the powder addition funnel, the three-necked flask was placed under nitrogen sealing through a suction stopper three-way coke.

100 ml of hexane was added to the three neck flask using a glass syringe. While the hydrochloric acid salt of triethylamine was slowly dropped in a three neck flask over 10 minutes while stirring at a rotational speed of 1,000 rpm with a magnetic stir bar, stirring was continued for 2 hours.

Thereafter, the reaction mixture was taken out in a separate container by pressure feeding using a cotton wool (Japanese Pharmacopoeia cotton wool cotton) stuffed at the front end of the polytetrafluoroethylene tube, followed by a membrane filter having a pore diameter of 0.1 µm made of polytetrafluoroethylene. It filtered by (Whatman Inc. make). The filtrate was received in a 300 ml eggplant flask, and after completion of the filtration, a magnetic stirrer was put in and a suction stopper three-way cock was attached.

This suction stopper 3-way coke was connected to the vacuum pump through a trap, and the solvent was removed at reduced pressure, stirring at 300 rpm by the magnetic stirring rod. After the solvent was removed, the residue was filtered using a membrane filter (manufactured by Whatman Inc.) having a pore diameter of 0.1 μm made of polytetrafluoroethylene to obtain 10.25 g of a complex of triethylamine and aluminum hydride as a colorless transparent liquid. In addition, the yield was 55%.

[Synthesis Example 4]

5 g of lithium aluminum hydride was suspended in benzene (80 ml), cooled to 5 ° C., and then a mixture of methylamine hydrochloride and ethylamine hydrochloride, which had been dried under reduced pressure for 2 hours in advance, was added. In addition, the molar ratio of methylamine hydrochloride and ethylamine hydrochloride added here was 3: 1. The amount of the mixture of methylamine hydrochloride and ethylamine hydrochloride to lithium aluminum hydride was such that the molar ratio with lithium aluminum hydride was 1: 1. After stirring at 5 ° C for 1 hour, the suspension was gradually heated up to 80 ° C. At that time, it was kept for about 1 hour at 50 degreeC. After refluxing at 80 DEG C for 18 hours, the precipitate containing lithium chloride and the insoluble reactant was removed by filtration, and benzene was removed under reduced pressure from the filtrate to obtain a white solid, which is a mixture of methyliminoalan and ethyliminoalan, 7.5. g was obtained. In addition, the yield was 94%.

[Production of Composition for Base Film Formation]

0.30 g of bis (penta-2,4-diketo) titanium (IV) diisopropoxide and 64 μL of tetrakis (dimethylamino) titanium are placed in a 20 ml glass jar, and propylene glycol monomethyl ether acetate is added thereto. The total amount of the mixture was 18.00 g. After the mixture was sufficiently stirred, the mixture was allowed to stand at room temperature for 2 hours. Subsequently, this was filtered using a membrane filter (manufactured by Whatman Inc.) having a pore diameter of 0.1 μm made of polytetrafluoroethylene to obtain a composition for forming a base film.

[Production of Composition for Forming Aluminum-Containing Film]

(1) Preparation of Composition A for Forming Aluminum-Containing Film

8.0 g of decane was added to 2.0 g of the aluminum complex obtained in Synthesis Example 1, and the mixture was sufficiently stirred, followed by standing at room temperature for 2 hours. Subsequently, this was filtered using a membrane filter (manufactured by Whatman Inc.) having a pore diameter of 0.1 µm made of polytetrafluoroethylene to obtain a composition A for forming an aluminum-containing film.

(2) Preparation of Composition B for Forming Aluminum-Containing Film

After 8.0 g of 4-methylanisole was added to 2.0 g of the aluminum complex obtained in Synthesis Example 2, the mixture was sufficiently stirred and then allowed to stand at room temperature for 2 hours. Subsequently, this was filtered using a membrane filter (manufactured by Whatman Inc.) having a pore diameter of 0.1 μm made of polytetrafluoroethylene to obtain a composition B for forming an aluminum-containing film.

(3) Preparation of Composition C for Forming Aluminum-Containing Film

9.0 g of 4-methylanisole was added to 1.0 g of the aluminum complex obtained in Synthesis Example 3, and the mixture was sufficiently stirred, followed by standing at room temperature for 2 hours. Subsequently, this was filtered using a membrane filter (manufactured by Whatman Inc.) having a pore diameter of 0.1 μm made of polytetrafluoroethylene to obtain a composition C for forming an aluminum-containing film.

(4) Preparation of Composition D for Forming Aluminum-Containing Film

9.0 g of toluene was added to 1.0 g of the iminoalan mixture obtained in the synthesis example 4, and after stirring the mixture sufficiently, it was left to stand at room temperature for 2 hours. Subsequently, this was filtered using a membrane filter (manufactured by Whatman Inc.) having a pore diameter of 0.1 μm made of polytetrafluoroethylene to obtain a composition D for forming an aluminum-containing film.

[Formation of Aluminum-containing Film]

Example 1

(1) A 4 inch silicon substrate was mounted in a spin coater, and 1 ml of the base film-forming composition was added dropwise under a nitrogen gas atmosphere, and spun at 10 rpm for 10 seconds. The substrate was placed on a hot plate set at 150 ° C and heated for 2 minutes. The thickness of the base film was 5 nm.

(2) Subsequently, the substrate was mounted on the spin coater again under a nitrogen atmosphere, and 2.5 g of the composition A for forming an aluminum-containing film was added dropwise thereto, followed by spin for 10 seconds at a rotational speed of 1400 rpm. The substrate was heated on a 150 ° C. hotplate for 5 minutes.

(3) Then, the board | substrate was heated at 500 degreeC in the furnace of nitrogen atmosphere for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Example 2]

The board | substrate obtained by performing the procedure similar to (1) and (2) of Example 1 was heated at 500 degreeC in the furnace of ammonia gas atmosphere (760 torr) for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Example 3]

The board | substrate obtained by performing the procedure similar to (1) and (2) of Example 1 was heated at 500 degreeC in the furnace of air atmosphere for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

Example 4

The board | substrate obtained by performing the procedure similar to (1) and (2) of Example 1 was heated at 500 degreeC in the furnace of the steam atmosphere (760 torr) for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Example 5]

By Example 1 (1) and (2) and into the substrate obtained by performing the procedures in the same way, in a closed pressure vessel containing a 10% NH ₃ aqueous solution of 100 g, introducing the furnace having an atmosphere of 170 ℃, ammonia generated in the container Steam and water vapor were exposed over 3 hours under pressurization, and hydrothermal treatment was performed.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Example 6]

(1) A 4-inch silicon substrate was placed on a hot plate set at 150 deg. C and heated for 2 minutes to remove moisture adsorbed on the surface.

(2) Subsequently, this board | substrate was attached to the spin coater in nitrogen atmosphere, 2.5 g of the said aluminum containing film formation compositions B were dripped, and it spun for 10 second at 1400 rpm. The substrate was heated on a 150 ° C. hotplate for 5 minutes.

(3) Then, the board | substrate was heated at 500 degreeC in the furnace of nitrogen atmosphere for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Example 7]

The board | substrate obtained by performing the procedure similar to (1) and (2) of Example 6 was heated at 500 degreeC in the furnace of ammonia gas atmosphere (760 torr) for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Example 8]

The board | substrate obtained by performing the procedure similar to (1) and (2) of Example 6 was heated at 500 degreeC in the furnace of air atmosphere for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Example 9]

The board | substrate obtained by performing the procedure similar to (1) and (2) of Example 6 was heated at 500 degreeC in the furnace of the steam atmosphere (760 torr) for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Example 10]

By Example 6 (1) and (2) and into the substrate obtained by performing the procedures in the same way, in a closed pressure vessel containing a 10% NH ₃ aqueous solution of 100 g of introducing a furnace having an atmosphere of 170 ℃, ammonia generated in the container Steam and water vapor were exposed over 3 hours under pressurization, and hydrothermal treatment was performed.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

Comparative Example 1

(1) A 4 inch silicon substrate was mounted in a spin coater, and 1 ml of the base film-forming composition was added dropwise under a nitrogen gas atmosphere, and spun at 10 rpm for 10 seconds. This board | substrate was put on the hotplate set to 150 degreeC, and it heated for 2 minutes. The thickness of the base film was 5 nm.

(2) Subsequently, this board | substrate was attached to the spin coater in nitrogen atmosphere, 2.5 g of the said aluminum containing film formation compositions C were dripped, and it spun for 10 second at 1400 rpm. The substrate was heated on a 150 ° C. hotplate for 5 minutes.

(3) Then, the board | substrate was heated at 500 degreeC in the furnace of air atmosphere for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

Comparative Example 2

Comparative Example 1 (1) and (2) and into the substrate obtained by performing the procedures in the same way, in a closed pressure vessel containing a 10% NH ₃ aqueous solution 100 g, the introduction of a furnace having an atmosphere of 170 ℃, ammonia generated in the container Steam and water vapor were exposed over 3 hours under pressurization, and hydrothermal treatment was performed.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

[Comparative Example 3]

(1) A 4-inch silicon substrate was placed on a hot plate set at 150 deg. C and heated for 2 minutes to remove moisture adsorbed on the surface.

(2) Subsequently, this substrate was mounted in a spin coater under a nitrogen atmosphere, and 2.5 g of the composition D for forming an aluminum-containing film was added dropwise thereto, followed by spin for 10 seconds at a rotational speed of 1400 rpm. This substrate was heated for 5 minutes with a 150 degreeC hotplate.

(3) Then, the board | substrate was heated at 500 degreeC in the furnace of air atmosphere for 1 hour.

The film thickness of the film thus obtained was analyzed using a cross-sectional SEM (scanning electron microscope), and the composition of the film was analyzed using RBS analysis (Rutherford backscattering analysis). The results are shown in Table 1.

From the result of Table 1, when heat-processing in nitrogen atmosphere or ammonia atmosphere using the composition for aluminum containing film formation of this invention, an aluminum nitride film can be obtained. On the other hand, an aluminum oxide film can be obtained when the heat treatment is performed in an air or steam atmosphere using the composition for forming an aluminum-containing film of the present invention or when the hydrothermal treatment is performed.

Particularly, when Examples 3 and 8 and Comparative Examples 1 and 3 are compared, even when heat treatment is performed in air having a relatively low oxidizing power, a high purity aluminum oxide film can be obtained when the composition for forming an aluminum-containing film of the present invention is used. Can be. This is considered to be due to the high reactivity of the organoaluminum compound which has a structure represented by the said General formula (1).

Claims (11)

An aluminum-containing film-forming composition containing an organoaluminum compound having a structure represented by the following formula (1) and an organic solvent.

(In formula (1), R ¹ to R ⁶ may be a hydrogen atom or a hydrocarbon group, may be the same or different, and R ⁿ (n is an integer of 1 to 6) may be connected to each other. A coating step of applying the composition for forming an aluminum-containing film according to claim 1 to form a coating layer on the substrate;
Forming an aluminum-containing film comprising a curing step of forming an aluminum nitride film by subjecting the coating layer to at least one selected from the group consisting of heating, electron beam irradiation, ultraviolet irradiation and plasma under an inert gas or reducing gas atmosphere. Way. The method for forming an aluminum-containing film according to claim 2, wherein the base is coated with a film containing aluminum or a transition metal on the surface of the base body. A coating step of applying the composition for forming an aluminum-containing film according to claim 1 to form a coating layer on the substrate;
A method of forming an aluminum-containing film comprising a curing step of forming an aluminum oxide film by subjecting the coating layer to at least one selected from the group consisting of heating, electron beam irradiation, ultraviolet irradiation and plasma under an oxidizing atmosphere. The method for forming an aluminum-containing film according to claim 4, wherein the base is coated with a film containing aluminum or a transition metal on the surface of the base body. The method for forming an aluminum containing film according to claim 4, wherein the oxidative atmosphere is an oxidizing gas atmosphere. The method for forming an aluminum-containing film according to claim 6, wherein the base is coated with a film containing aluminum or a transition metal on the surface of the base body. The method for forming an aluminum containing film according to claim 4, wherein the oxidative atmosphere is an air atmosphere. The method for forming an aluminum-containing film according to claim 8, wherein the base is coated with a film containing aluminum or a transition metal on the surface of the base body. A coating step of applying the composition for forming an aluminum-containing film according to claim 1 to form a coating layer on the substrate;
A film forming step of forming a film containing carbon and aluminum by subjecting the coating layer to at least one treatment selected from the group consisting of heating, electron beam irradiation, ultraviolet irradiation and plasma;
A method of forming an aluminum-containing film comprising a post-treatment step of forming an aluminum oxide film by subjecting the film obtained in the film forming step to a hydrothermal treatment. The method for forming an aluminum-containing film according to claim 10, wherein the base is covered with a film containing aluminum or a transition metal on the surface of the base body.